Narrative:

Flight was on the jasen four arrival to iad; 5 mi west of the gilby intersection; descending through 6500 ft with clearance to 6000 ft; at XA38Z nov/xa/07. TCAS system issued a TA advisory for opposite direction converging traffic climbing toward us. At approximately 6200 ft altitude and 800 ft vertical separation a climb RA was issued by the TCAS. The captain responded by disengaging the autoplt and initiating a climb to comply with RA. During the RA maneuver ATC reported traffic 12 O'clock position; X mi turn right heading xx. Crew responded climbing for TCAS RA and complied with the ATC assigned turn. Closest observed separation on the TCAS was 1-2 mi and 500 ft. The TCAS target appeared to continue its climb throughout the event. We never had visual contact with the alert aircraft. Supplemental information from acn 762034: the event occurred I believe due to poor planning on the potomac approach controller who allowed the aircraft departing dulles airport to continue its climb straight ahead while we were only 2000 ft above the initial altitude cleared for any departures from the airport.

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Original NASA ASRS Text

Title: E145 FLT CREW DESCENDING TO 6000 FEET ON THE JASEN 4 ARRIVAL TO IAD COMPLY WITH TCAS RA FOR TRAFFIC CLIMBING THROUGH THEIR ALTITUDE. ATC ALSO ASSIGNS HEADING TO INCREASE SEPARATION.

Narrative: FLT WAS ON THE JASEN FOUR ARR TO IAD; 5 MI W OF THE GILBY INTXN; DSNDING THROUGH 6500 FT WITH CLRNC TO 6000 FT; AT XA38Z NOV/XA/07. TCAS SYS ISSUED A TA ADVISORY FOR OPPOSITE DIRECTION CONVERGING TFC CLBING TOWARD US. AT APPROX 6200 FT ALT AND 800 FT VERT SEPARATION A CLB RA WAS ISSUED BY THE TCAS. THE CAPT RESPONDED BY DISENGAGING THE AUTOPLT AND INITIATING A CLB TO COMPLY WITH RA. DURING THE RA MANEUVER ATC RPTED TFC 12 O'CLOCK POS; X MI TURN R HDG XX. CREW RESPONDED CLBING FOR TCAS RA AND COMPLIED WITH THE ATC ASSIGNED TURN. CLOSEST OBSERVED SEPARATION ON THE TCAS WAS 1-2 MI AND 500 FT. THE TCAS TARGET APPEARED TO CONTINUE ITS CLB THROUGHOUT THE EVENT. WE NEVER HAD VISUAL CONTACT WITH THE ALERT ACFT. SUPPLEMENTAL INFO FROM ACN 762034: THE EVENT OCCURRED I BELIEVE DUE TO POOR PLANNING ON THE POTOMAC APCH CTLR WHO ALLOWED THE ACFT DEPARTING DULLES ARPT TO CONTINUE ITS CLB STRAIGHT AHEAD WHILE WE WERE ONLY 2000 FT ABOVE THE INITIAL ALT CLRED FOR ANY DEPS FROM THE ARPT.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.